This invention relates to nucleic acid and amino acid sequences of a new human embryogenesis protein and to the use of these sequences in the diagnosis, prevention, and treatment of inflammation and disorders associated with cell proliferation and apoptosis.
Mammalian embryogenesis is a process which encompasses the first few weeks of development following conception. During this period, embryogenesis proceeds from a single fertilized egg to the formation of the three embryonic tissues, then to an embryo which has most of its internal organs and all of its external features.
The normal course of mammalian embryogenesis depends on the correct temporal and spatial regulation of a large number of genes and tissues. These regulation processes have been intensely studied in mouse. For example, spindlin (Spin) is an abundant maternal transcript present in the unfertilized egg and 2-cell stage embryo. Spindlin functions in cell-cycle regulation during the transition from gamete to embryo; its activity is modulated by cell cycle-dependent phosphorylation (Oh, B. et al. (1997) Development 124: 493-503). Another maternal transcript, Mem3 is abundant in the unfertilized egg and the newly formed zygote (Hwang, S. et al. (1996) Mamm. Genome 7: 586-590). The amino acid sequence of Mem3 resembles the yeast vacuolar protein sorting 35 (VPS35), a protein involved in the intracellular sorting of proteases and hydrolases. Many of the lysosomal storage diseases in human and other mammals appear to be caused by incorrect sorting of the lysosomal hydrolases. Still another maternally transcribed protein, Maid, is shown to be a negative regulator of basic helix-loop-helix (bHLH) proteins (GI1255172). bHLH proteins are a group of transcription factors which play a pivotal role in cell differentiation, tissue-specific determination, and embryogenesis. Dysregulated expression or loss of function of these bHLH protein have been correlated with the development of leukemia and tumors (Gitelman, I. (1997) Dev. Biol. 189: 205-214; Rostomily, R. C. et al. (1997) Cancer Res. 57: 3526-3531).
The discovery of a new human maternally transcribed protein and the polynucleotides encoding it satisfies a need in the art by providing new compositions which are useful in the diagnosis, prevention and treatment of inflammation and disorders associated with cell proliferation and apoptosis.
The invention features a substantially purified polypeptide, the maternally transcribed protein (HMTP), having the amino acid sequence shown in SEQ ID NO:1, or fragments thereof.
The invention further provides an isolated and substantially purified polynucleotide sequence encoding the polypeptide comprising the amino acid sequence of SEQ ID NO:1 or fragments thereof and a composition comprising said polynucleotide sequence. The invention also provides a polynucleotide sequence which hybridizes under stringent conditions to the polynucleotide sequence encoding the amino acid sequence SEQ ID NO:1, or fragments of said polynucleotide sequence. The invention further provides a polynucleotide sequence comprising the complement of the polynucleotide sequence encoding the amino acid sequence of SEQ ID NO:1, or fragments or variants of said polynucleotide sequence.
The invention also provides an isolated and purified sequence comprising SEQ ID NO:2 or variants thereof In addition, the invention provides a polynucleotide sequence which hybridizes under stringent conditions to the polynucleotide sequence of SEQ ID NO:2. The invention also provides a polynucleotide sequence comprising the complement of SEQ ID NO:2 or fragments or variants thereof.
The present invention further provides an expression vector containing at least a fragment of any of the claimed polynucleotide sequences. In yet another aspect, the expression vector containing the polynucleotide sequence is contained within a host cell.
The invention also provides a method for producing a polypeptide comprising the amino acid sequence of SEQ ID NO:1 or a fragment thereof, the method comprising the steps of: a) culturing the host cell containing an expression vector containing at least a fragment of the polynucleotide sequence encoding HMTP under conditions suitable for the expression of the polypeptide; and b) recovering the polypeptide from the host cell culture.
The invention also provides a pharmaceutical composition comprising a substantially purified HMTP having the amino acid sequence of SEQ ID NO:1 in conjunction with a suitable pharmaceutical carrier.
The invention also provides a purified antagonist of the polypeptide of SEQ ID NO:1. In one aspect the invention provides a purified antibody which binds to a polypeptide comprising the amino acid sequence of SEQ ID NO:1.
Still further, the invention provides a purified agonist of the polypeptide of SEQ ID NO:1.
The invention also provides a method for stimulating cell proliferation comprising administering to a cell an effective amount of purified HMTP.
The invention also provides a method for preventing or treating a disorder associated with an increase in apoptosis comprising administering to a subject in need of such treatment an effective amount of a pharmaceutical composition comprising purified HMTP.
The invention also provides a method for preventing or treating a cancer comprising administering to a subject in need of such treatment an effective amount of an antagonist of HMTP.
The invention also provides a method for preventing or treating an inflammation comprising administering to a subject in need of such treatment an effective amount of an antagonist of HMTP.
The invention also provides a method for detecting a polynucleotide which encodes HMTP in a biological sample comprising the steps of: a) hybridizing the complement of the polynucleotide sequence which encodes SEQ ID NO:1 to nucleic acid material of a biological sample, thereby forming a hybridization complex; and b) detecting the hybridization complex, wherein the presence of the complex correlates with the presence of a polynucleotide encoding HMTP in the biological sample. In one aspect the nucleic acid material of the biological sample is amplified by the polymerase chain reaction prior to hybridization.